math help

What is 24/5 + 4/12?

What is 24/5 + 4/12?

This is how we add

24
5
+
4
12

Step 1

We still have different denominators (bottom numbers), though, so we need to get a common denominator. This will make the bottom numbers match. Multiply the denominators together first. Now, multiply each numerator by the other term's denominator.

Now we multiply 24 by 12, and get 288, then we multiply 5 by 12 and get 60.

24/5 times 12

Now for the second term. You multiply 4 by 5, and get 20, then multiply 5 by 12 and get 60.

4/12 times 5

This gives us a new problem that looks like so:

288
60
+
20
60

Step 2

Since our denominators match, we can add the numerators.

288 + 20 = 308

So what's the answer so far?

308
60

Step 3

Can this fraction be reduced?

First, we attempt to divide it by 2...

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

308
60
÷ 2 =
154
30

Let's try dividing by that again...

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

154
30
÷ 2 =
77
15

Let's try dividing by that again...

Nope! So now we try the next greatest prime number, 3...

Nope! So now we try the next greatest prime number, 5...

Nope! So now we try the next greatest prime number, 7...

Nope! So now we try the next greatest prime number, 11...

Nope! So now we try the next greatest prime number, 13...

Nope! So now we try the next greatest prime number, 17...

No good. 17 is larger than 15. So we're done reducing.

There you have it! Here's the final answer to 24/5 + 4/12

24
5
+
4
12
=
77
15
© 2014 Randy Tayler